Excuse.. Since the New Asset is a rural agricultural land, sale of such land does not attract capital gains, and the entire income is tax free.
Regarding 54F, exemption under the section can be availed of when u invest LONG Term Capital Gains. In your case, in AY 2012 - 13, there is a balance of Rs 80,000 as LTCg if such amount is deposited in Capital Gains Account Deposit Scheme within the due date of filing return, and later utilised for purchase of House Property within a period of 2 years from the date on which the original transfer (initial sale) took place, then you will be eligible to claim exemption under this section. Kindly note that the section allows the claim of exemption, only if the assessee holds one residential house property OTHER than the New Residential Property being purchased on the date of Original Transfer.
I hope this clears your issue.
Warm Regards.